Thermochemical preparation of W–25%Cu nanocomposite powder through a CVT mechanism

In order to produce a W–25%Cu nanocomposite powder manufactured by a thermochemical procedure a novel pair of precursors were used. Cu2WO4(OH)2 and CuWO4·2H2O precipitates were first produced by reacting the copper nitrate and sodium tungstate aqueous solutions under certain pH and temperature. The precipitates were then dried and calcined in order to prepare CuWO4 − x, CuO, and WO3 oxide powders for the next step reduction. The reduction was carried out under a H2 atmosphere to form the final W–Cu metal nanocomposite powder. Characteristics of the final powder such as distribution, uniformity and size were then discussed based thoroughly on the dominant mechanism of reduction; Chemical Vapor Transport. It was found that the average particle size of the reduced powder is 35 nm for W and 54 nm for Cu.